Two second half goals sealed the win for the Hammers and sees them move up to third in the table, only one point behind new league leaders Colchester United Ladies.
Going into half time the match was goalless, with the home side having the better chances in the first period. But going into the second half the away side took control and sealed all three points.
West Ham opened the scoring in the 50th minute when Carly Roache collected a cross from the left to turn and shoot past the Keynsham Town goalkeeper. The Hammers’ second came after Jess Barling’s corner beat everyone and found the corner of the net.
The result sees the Hammers stay in the race for promotion although close rivals Portsmouth Ladies and Brighton and Hove Albion Ladies have a game in hand on West Ham.
Elsewhere in the league new leaders Colchester climbed to the top of the division with a 4-1 win over Gillingham Ladies, second-placed Portsmouth beat bottom side Millwall Lionesses 4-2 and Queens Park Rangers Ladies won 1-0 at Tottenham Ladies.